1. Field of the Invention
The present invention generally relates to electronic apparatus and, in a preferred embodiment thereof, more particularly relates to apparatus and methods for operatively mounting circuit boards on support structures such as computer chassis walls.
2. Description of Related Art
For many years, the conventional method of installing a circuit board, such as the motherboard, in a computer was to simply screw the board substrate to bosses or other mounting structures suitably mounted on a chassis wall portion of the computer. This circuit board installation method substantially increased the time, and thus the cost, required to construct the computer in addition to adding to the complexity and difficulty of assembling, and later disassembling and servicing the computer.
A relatively recent improvement in the mounting of a main circuit board in a computer is illustrated and described in U.S. Pat. No. 5,754,396 to Felcman et al entitled xe2x80x9cMODULAR DESKTOP COMPUTER HAVING ENHANCED SERVICEABILITY In the desktop computer illustrated and described in this patent, the motherboard is mounted on a tray structure which may be slid into and out of the computer chassis to install and later remove the motherboard for access and service purposes.
While this tray support concept hastens and reduces the cost associated with initially installing the motherboard in the chassis and subsequently removing the motherboard for service and replacement, it also increases the manufacturing cost of the computer since the motherboard must be produced and spared with this auxiliary support tray secured thereto.
It thus can be seen from the foregoing that it would be desirable to provide for the cost effective, screwless installation and removal of a circuit board within a computer without the necessity of securing to the computer an auxiliary support tray or other cost increasing mounting structure. It is to this design goal that the present invention is directed.
In carrying out principles of the present invention, in accordance with a preferred embodiment thereof, electronic apparatus is provided which is representatively in the form of a desktop computer. The computer has a circuit board, illustratively a motherboard, and a support structure, representatively a chassis wall. According to a key aspect of the present invention, the circuit board is operatively secured to the chassis wall without the use of screws or any sort of support tray secured to the circuit board.
Using a screwless Circuit board attachment technique of the present invention, cooperatively engaged locking structures are carried by the circuit board and the support structure. The cooperatively engaged locking structures releasably hold the circuit board on the support structure and permit removal of the circuit board from the support structure in response to sequential movement of the circuit board relative to the support structure in (1) a first direction and (2) a second direction transverse to the first direction. A retaining structure releasably blocks movement of the circuit board in the first direction relative to the support structure, thereby releasably retaining the circuit board on the support structure.
In a preferred embodiment of the screwless circuit board attachment apparatus, the openings have generally keyhole-shaped configurations and are formed in a substrate body portion of the circuit board, and the projections are carried on the chassis wall portion, extend partly through the substrate openings and have notch portions receiving opening edge portions of the substrate body portion.
To rapidly install the circuit board on the chassis wall projections, the substrate body openings are moved over outer end portions of the projections, and the substrate body is moved parallel to its plane to cause the opening edge portions to enter the notches on the projections and thereby block removal of the circuit board from the projections in a direction parallel to their lengths. A retaining bracket member is then moved into a position in which it blocks movement of the circuit board to move its opening edge portions out of the projection notches.
When it is later desired to remove the circuit board, the retaining bracket is simply moved away from its circuit board blocking position, the circuit board is moved transversely to the projections to remove its opening edge portions out of the projection notches, and the circuit board is lifted off the projections.